We already know that electric vehicles can significantly reduce emissions, merely by virtue of the fact that they can be recharged via renewable energy, but a new study suggests that their effect on emissions is greater than their own emissions reduction.
By themselves, electric vehicles generate zero emissions, but they also don’t generate nearly as much heat as conventional vehicles. Indeed, this is why conventional internal-combustion-engine (ICE) vehicles are so inefficient, because most of the energy in the fuel is lost as heat energy, which heads out the tailpipe into the atmosphere. Soot and other emissions are already a public health threat, and carbon dioxide is an abundant greenhouse gas, but the heat itself was the subject of a recent Michigan State University (MSU) and Hunan University, China.
Heat released from the combustion of automotive fuels creates a heat island effect, increasing urban temperatures relative to the surrounding suburbs. Increased temperatures, in turn, results in the need for additional air conditioning, which increases building operating costs and their carbon footprint. Also, in a kind of spiral effect, air conditioning usage adds more heat to the urban heat island. Once source of that heat, at the centre of the spiral, so to speak, is the transportation system.
Compared to ICE-driven conventional vehicles, battery electric vehicles generate just 20% of the heat. MSU and Hunan researchers calculated that, for the year 2012, switching conventional vehicles for electric vehicles could have reduced the urban heat island temperature, in Beijing, by 2.8 °F. This tiny drop in temperature would have had profound effects, reducing air conditioning needs for the entire city. In turn, judging by reduce air conditioning utilization, researchers calculated that energy expenditures would have been reduced by some 14.4 million kWh, reducing carbon dioxide emissions by 11,770 tons per day. Some factors, such as reduced smog-production factors, were not included in the study, which would probably have resulted in an even more profound effect on the urban heat island effect.
